There are no circular loop boundary strips because many different loop sizes would be needed. However, you can construct an approximation to a perfect circle by cutting up a strip into several short segments which can be arranged in a circle; draw the circle on paper to mark the angle at which the ends should be cut to fit flush together. Duck tape can be used on the back to join the segments, or double sided tape used to fasten them all to some backing or floor.

Note you cannot turn the strips on edge allowing making a loop, because the sensors will not detect the strips unless they are flat under the robot's recessed sensors.

There may be other solutions to your particular boundary problem. Describe the application and situation more fully to seek more advice.I would not rely on mag srips to protect pet water bowls, as spills are too damaging to the robot to risk any sensor failure or difficulty (such as backing up across it, where the only sensors are in the front). As mentioned in the Mods & Repairs list top of forum, physical barriers are recommended for any water bowls.

The Samsung strips are narrow and have self-stick bottoms for gluing to the floor. They are magnetically the same as Neato (all the bots use the same). Being narrow and thin they might bend around corners or into a circle. Expensive though, $31 for 3 feet. Part# DJ97-00635D at Samsungparts.com in the U.S.; press ENTER in the part# field, not the search icon (other distributors in other countries -- contact Samsung customer service for references). They are shown in the Powerbot manuals installed in a rectangle, but whether cut for that or bent at the corners unknown (I don't use them -- I actually use Neato strips with a Powerbot).